1. Field of the Invention
This invention generally relates to a mobile apparatus for shaking trees or bushes to remove fruits or nuts therefrom and more particularly concerns an improved tree shaking apparatus of the type which is moved along a generally straight path from a shaking position beside one tree in a row of trees to a shaking position beside the next tree in the same row of trees.
2. Brief Description of the Prior Art
In the past various types of mobile tree shaking devices have been used in the harvesting of fruits and nuts. Basically, the devices are either of the "in-and-out" type or the "down-the-row" type. An example of the former type is disclosed in U.S. Pat. No. 3,457,712 to R. D. Gould et al. The disclosed device includes a carrier vehicle having an articulated boom assembly extending longitudinally from the front of the operator's cab, a suspension unit mounted to a boom, and a tree shaking and clamping assembly resiliently suspended from the suspension unit. In the operation of this type of mobile tree shaker, the carrier vehicle is first moved inwardly toward the tree to be shaken until the vehicle is close enough to the tree so that the trunk thereof may be grasped by the clamping arms of the shaking and clamping assembly. After the tree has been shaken and the clamping arms disengaged from the tree, the vehicle is moved outwardly along the same path taken when moved into the shaking position adjacent the tree, and thereafter the vehicle is turned and driven down the row of trees to the next tree in the row. Obviously, it is from this manner of travel relative to the tree to be shaken that the shaker is known as an "in-and-out" type of tree shaker.
It will be appreciated that when the rows of trees to be harvested are tightly spaced, it is difficult to manuever the "in-and-out" type of tree shaker. Another major problem is the risk of injury to field workers during the course of harvesting a row of trees when the vehicle is withdrawn from a tree.
The aforementioned "down-the-row" type of shakers generally include a tree shaking and clamping assembly which is mounted to a carriage which, in turn, is mounted to a support frame so that the tree shaking and clamping assembly may be moved inwardly and outwardly relative to the carrier vehicle along a path which is transverse to the longitudinal axis of the vehicle. The carrier vehicle is driven along a path which is parallel to the row of trees to be harvested; and after positioning the vehicle in a position transversely aligned with a tree in the row to be shaken, the carriage is activated to outwardly extend the shaking and clamping assembly to a position such that the clamping arms may be actuated to engage the trunk of the tree. This "down-the-row" mode of harvesting will be appreciated to be safer since it is not necessary that the vehicle be backed away from a tree. Also, this mode permits harvesting of orchards having relatively small transverse spacings between the rows of trees in the orchard.
Examples of this latter type of tree shaking apparatus are illustrated and described in U.S. Pat. Nos. 3,683,617 to Vallicella and 3,477,215 to Herbst. It is noted that both of these patents illustrate a combination of a "down-the-row" tree shaking apparatus and also a catch frame and conveyor means mounted to the carrier vehicle for accumulating the detached fruits or nuts and storing the same in a bin carried on the vehicle.
It will be recognized that the aforementioned transversely movable carriage assembly, which supports the shaking and clamping assembly, is a relatively complex structure which is relatively expensive to manufacture and maintain. Moreover, in the operation of such prior art down-the row tree shakers, it is difficult for the operator thereof to determine when the vehicle is in a location which is transversely aligned with the trunk of the tree to be shaken so that the carriage may be extended outwardly to move the shaking assembly to a shaking position adjacent the tree trunk. Thus, oftentimes the operator will stop at a position improperly aligned with a tree to be harvested, and, upon actuating the carriage, the outer ends of the clamping arms, or the nearby parts of associated catch frame assembly, will strike the tree, thereby damaging the tree and also perhaps the clamping arms or the associated catch frame apparatus, and also necessitating a withdrawal of the carriage and a repositioning of the vehicle to correct the misalignment condition.